Combination casing-head and oil-saver.



G. F. RIGBY.

COMBINATION CASING HEAD AND OIL SAVER.

APPLICATION FILED PBB.7, 1913. RENEWED D30. 3]., 1913 1 l 05, 340.

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0. F. RIGBY.

COMBINATION CASING HEAD AND OIL SAVER.

APPLICATION FILED FEBHY, 191s. RENEWED DBO. 31,1913.

Patented July 28,1914,

2 SHEETS SHEET 2.

FIG.3.

WITNESSES: I

- G7 I INVIENTOR I f I I r I Attv GEAR-E F.

RIGEY, 0F BUTLER, PENNSYLVANIA.

CQTvIBINATIQN CASING HEAD AND QILNSAVERQ Specification of Letters Patent.

Patented July 28, little.

implication filed February 7, 191a, serial No. reacts. Renewed December 31, 1913. serial No. 8.093760.

an integral structure which is adapted to connect with the internally threaded collar carried by the upper end of every section of well casing, the composite structure being of such form that it may be applied to the casing or removed therefrom without removing or disturbing the drilling cable.

The structural features of the invention are of importance in view of the conditions at tending the drilling of deep wells in certain oil producing regions as hereinafter explained.

in the oil fields of Pennsylvania and adjacent territory casing heads oithe general type shown in my Patent No. 9833M, February 7, 1911, are used, the casing be ng supported at its lower end. Frequently,

only the surface portion of a well is cased, the casing being used as an adjunct of the well inclosing mechanism or for shutting oil water channels which the well intersects, this being accomplished by the use of suitable packers, all as well understood in the art. different condition is encountered in some of the Western and southern oil fields, notably in California, Louisiana, and elsewhere where the formations are such that the casing must closely follow the advance of the drilling tools to prevent the unsulostantial walls of the drilled hole from caving in and filling or obstructing the well and entrapping the tools. In those regions underreaming tools are largely used, the latter deriving their name from the fact that they operate beneath the extremity of the casing, cutting away the formation in the path of the casing so that it may be lowered'progressively as the work proceeds and thereby forestall caving. The very nature of this procedure precludes supporting the casing at its lower end and hence supporting means must be provided at the surface, and the arrangement must be such that the casing may be lowered from time to time to maintain it in relatively close proximity to the hole forming tool The casing supporting means at the surface precludes the employment of a casing head of the type shown in my former patent because it is too large to be embraced by the casing supporting elevators, and for the furtherreason that the elevators must operate in conjunction with the steel collar at the upper end of each succeeding casing section. Gasing heads of former design are constructed of cast iron and are not adapted to cooperate with casing collars as they are threaded internally for connecting with the casing after 'the collar has been removed. And even it the casing head of former design were suflicie'ntly small to permit the elevator links to extend therearound with the body of the elevator engaging the under side of the head, (an expedient not heretofore proposed nor suggested) the enormous.

weight of the casing would cause it to strip from the cast iron casing head and drop into the well. In view of the limitations of casing closures heretofore proposed, closures are not ordinarily used during the operation of vdrilling in the regions to which I have referred with the result that there is very considerable waste. And the presence of this outfiowing oil greatly hampers the progress of the work and creates conditions that are almost intolerable for the drillers and others engaged in sinking such wells. The present invention overcomes these difiicuties by providing a composite casing head and oilsaver which may he used without interfering with the casing supporting mechanism, and which may he applied to or removed from the casing without withdrawing the tools or cutting the cable.

In the accompanying drawings, Figure 1 is an elevation of a portion of the well drilling apparatus commonly employed in the regions to which l have referred, my improved closure heing shown in connection therewith, the several parts being illustrated as they appear when drilling is in progress. Fig. 2 is a similar view illustrating the casing suspended from above as when the sup porting jacks are being adjusted. Fig. 3 is a. View of the improved closure shown partly in elevation andpartly in section, and Fig. l is avertical longitudinal section taken at right angles to Fig. 3. Figs. 5 and 6 are cross-sections taken on lines 55 and 6-6, respectively cit 3.

Referring to the drawings, body 2 of the casing head is hollow and is formed with a depending annular verticall -open extension 3, externally threaded as in icated at 4. At opposite sides of body 2 are the lateral oil outlets 5 to ,which flexible pipes .6 may be connected for conducting ofi' the outflowing oil. At the top of body 2 is the integral upward extension 7 which is raised to form the stuffing box cavity 8, a cable passage 9 connecting the stufling box with the interior of body 2. Cavity 8 is threaded internally for receiving the two-part gland-nut 10, the latter being of the construction shown and described in my above mentioned patent of February 7 1911, the nut operating to compress packing 11 in cavity 8 around the drillin cable C. A The structure thus far describe comprises a composite casing head and oil saver, body 2 closing the casing and directing the oil through the outlet pipes, and body extension 7 and the stufiing box embodied therein comprising an oil saver which prevents outflow around the cable.

Formed through one side of body 2 and stuifing box extension 7 is the vertical slot 12 which extends from top to bottom of they structure and intersects stuffing box cavity 8 and cable passage 9. By means of this slot the combined casing head and oil saver may be applied to and removed from the casing and cable without withdrawing the latter and the tools, and of course without severing the cable. Slot 7 is closed by'the flat or plate-like device 13 which is securedb. bolts 14 extending through lugs on the b0 y and closure as shown. The inner face of the upper portion of the closure 13 is threaded at 15 so that the threads in stufiing box 8 may be continuous or unbroken when the closure is in place. Likewise the lower portion of the closure is threaded externally at 16 so that the threads of body extension 3 are continuous or unbroken. Ring 17 at the upper portion of closure 13 may be utilized for conveniently handling the latter.

A characteristic of the invention is its externally threaded bottom extension 3 whereby the entire device may be coupled with the internally threaded steel collar B of the well casing A. In practice, each length or section of casing is always provided at its upper end with a coupling collar for uniting with the casing length next above, and in the oil producing regions hereinbefore referred to the presence of this collar on the upper? most casing length is essential, and it is therefore necessary to so form the casing head that it will connect therewith instead of directly with the casing, as shown in my above mentioned patent.

In the practlce and use to which reference .has been made, the entire casing-reaching to hundreds and even thousands of feet must be supported at the surface of the ground, and this is ordinarily accomplished by the use of elevators D provided with the progressively as the drilling proceeds.

swinging links E, all of familiar construction. The elevators are closed around the casing beneath collar B, the latter'constitut ing a supporting shoulder. Normally, the elevators are supported from beneath by jacks F which rest on blocks Gr, the latter being built up from the bottom of cavit H formed in the earth beneath a derrick oor J as in full lines in Fig. 1, or after a new section of the casingis inserted the blocks may be supported by the derrick floor, as in dotted linesin Fig. 1. As heretofore described,wit is necessary to lower the casing This is accomplished in the first instance by starting'with the lifting jacks projected upwardly as far as possible and lowering them the full length of their throw. WVhen it is necessary to remove one or more sets of blocks G in order to support the jacks at a lower level the weight is supported by a suitable cable K in the derrick provided with a hook-K that engages theelevator links E, as in Fig. 2, and incident to this feature of the operation a further characteristic of the invention. is the relatively small and compact form of the casing closure which permits of links E swinging upwardly therearound in position to be supported by cable K. Suchmanipulation would be impossible with the casing head of my former patent as it is too large to permit the supporting links to close together. And the casing head of that patent is necessarily relatively large to accommodate the removable oil saver.

Derrick floor J is open so that the casing head and elevators may move. therethrough, the opening being spanned by the supporting blocks G when the mechanism is in elevated position, as in dotted lines in Fig. 1. As oil outlet pipes 6 are flexible, being preferably in the'form of large hose, they accommodate themselves to the composite casing head and oil saver regardless of its position or elevation.

It is of course necessary to remove the casing head and oil saver in order that the tools and drilling cable may be withdrawn whena new length of casing is to be applied. As a general rule the flow of oil is intermittent, and when possible the casing lengths are put in place at periods when the flow has ceased. But even if it is necessary to apply new sections when the, well is flowing, the latter is open for only a short period, at" all other times the casing being closed, preventing waste and protecting the workmen, results that have not been attained heretofore in those-oil producing regions in which on account of the formation of the earth the casingmu'st closely 'follow the drilling and be so ported from above.

I c aim 1. A casing closure open at its lower end and adapted to connect with a well casing and provided, with a lateral oil outlet, the upperportion of the closure formed with a cable passage, cable packing means for the passage, the casing closure formed with a cable entering slot which extends from top to bottom thereof, and slot closing means. 2. A casing closure consisting of a hollow body open at its lower end and adapted to connect with a well casing and provided with a lateral oil outlet, the upper portion of the body'formed with an integral vertically open stuffing box, packing compress ing means for the box, the body including the integral stufling box formed with a cable inserting slotextendi-n from top to bottom thereof, and a closure or the slot.

3. A casing closure consisting of a hollow body having a vertically open externally threaded lower portion adapted to connect with the internally threaded collar of a well casing, the body provided with a lateral oil outlet, the upper portion of the body contracted and formed with a cable passage, means within the passage for packing a drilling cable, the body and its contracted upper portion formed with a cable insertin slot extendin from top to bottom thereo' with the slot lntersecting said passage, and a closure for the slot.

4. A casing closure consisting of a hollow body havin an'open downwardly extending externally t readed portion adapted to connect with a well casin collar, the booyihaving a lateral oil out et, a Vertically open stuffing box integral }with the body and forming an upwardcontinuation thereof, the

threaded collar,

ing of a hollow body open at its bottom and ing box and the lower portion of the closure shaped toconform to the lower portion of the body with the outer face of the closure threaded complementary with the threaded lower ortion of the body, and vertically divided packing compressing means for the stuffing box adapted to removably embrace the cable.

5. The combination with a Well casing provided at its upper end with an internally o a casing closure consistthreaded externally around the bottom opening for entering and coupling with the internally threaded collar,- the body formed with an oil outlet and also open at'its top to receive a drilling cable, a closure adapted to removably embrace a drilling cable and close the said top opening, the hollow body formed with a cable-entering slot communicating with the top and bottom openings therein, and aclosure removably secured in the slot and conforming in shape to the upper and lower'portions of the body.

In testimony whereof I afiix my signature in presence of two witnesses.

J. M. NEsBrr, F. E. \GAITH'ER. 

